Anthrax is typically the work of a bacterium called Bacillus anthracis, which produces a cocktail of powerful and lethal toxins. But the microbe that attacked the chimps was a new strain of Bacillus cereus, which had acquired many of the same toxin genes. Very little is known about this strain of rainforest anthrax, known as Bcbva. But Leendertz and his colleagues from the Robert Koch Institute in Berlin have now shown that it’s a startlingly prolific killer, responsible for more than a third of mammalian deaths in the Taï forest. And it is likely to wipe out the local chimpanzees within the next 150 years.